Image transfer and output method and system using the same

ABSTRACT

A plurality of original image signals representing radiation image information, which have been fed out from an image signal input apparatus, are fed into an operation processing device. Predetermined operation processing is performed on the plurality of the received original image signals in the operation processing device to obtain an operation-processed image signal. Also, at least one original image signal, which is among the plurality of the original image signals, is transferred to an image output device. Image outputting is performed with the image output device and in accordance with the one original image signal having been transferred. After the operation-processed image signal has been obtained from the predetermined operation processing, the operation-processed image signal is fed into the image output device, and image outputting is performed with the image output device and in accordance with the received operation-processed image signal.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an image transfer and output method and animage transfer and output system. This invention also relates to animage signal input terminal and an image output terminal for use in theimage transfer and output system.

2. Description of the Related Art

In various fields, such as the medical field, techniques for reading outa radiation image of an object, which has been recorded on a stimulablephosphor sheet or film, to obtain an image signal, performingpredetermined image processing on the image signal, and thereafterdisplaying a visible image, which is reproduced from the processed imagesignal, on an image display device, such as a cathode ray tube (CRT)display device, or outputting the visible image on film with a printer,such as a laser printer (LP), have heretofore been utilized.

Particularly, recently, digital image processing techniques utilizingcomputers have been developed. Also, various image forming apparatuses(image forming modalities) utilizing the digital image processingtechniques have been used in practice as the apparatuses for formingimages for use in making a diagnosis, and the like. As such imageforming modalities, computed tomography (CT) scanners, magneticresonance imaging (MRI) apparatuses, computed radiography (CR)apparatuses, and the like, have been used in practice. The reproducedvisible image is utilized for making a diagnosis, e.g. for investigatingthe presence or absence of a diseased part or an injury or forascertaining the characteristics of the diseased part or the injury.

The CR apparatuses are radiation image recording and read-outapparatuses. With the radiation image recording and read-outapparatuses, a radiation image of an object, such as a human body, isrecorded on a sheet provided with a layer of a stimulable phosphor(hereinafter referred to as a stimulable phosphor sheet). The stimulablephosphor sheet, on which the radiation image has been stored, is thenexposed to stimulating rays, such as a laser beam, which cause it toemit light in proportion to the amount of energy stored thereon duringits exposure to the radiation. The light emitted by the stimulablephosphor sheet, upon stimulation thereof, is photoelectrically detectedand converted into an electric image signal with photoelectric read-outmeans, such as a photomultiplier. Recently, the CR apparatuses arewidely used in practice.

As techniques for photoelectrically detecting light emitted by astimulable phosphor sheet, the applicant proposed techniques fordetecting light emitted from opposite surfaces of a stimulable phosphorsheet and thereby detecting two image signals from the opposite surfacesof the stimulable phosphor sheet in, for example, U.S. Pat. No.4,346,295 and Japanese Unexamined Patent Publication No. 8(1996)-116435.With the proposed techniques, two photoelectric read-out means arelocated respectively on opposite surface sides of the stimulablephosphor sheet. Also, stimulating rays are irradiated to the twosurfaces or only to one surface of the stimulable phosphor sheet, andthe light, which is emitted by the stimulable phosphor sheet when it isexposed to the stimulating rays, is photoelectrically detected on theopposite surface sides of the stimulable phosphor sheet.

Specifically, with the techniques for detecting light emitted fromopposite surfaces of a stimulable phosphor sheet and thereby detectingtwo image signals from the opposite surfaces of the stimulable phosphorsheet, a stimulable phosphor sheet is formed by overlaying a stimulablephosphor layer on a surface of a transparent substrate, and a radiationimage is stored on the stimulable phosphor sheet. The stimulablephosphor sheet, on which the radiation image has been stored, is fittedon a transparent holder, and two photoelectric read-out means arelocated respectively above and below the holder. In this state, thelight, which is emitted from one surface side of the stimulable phosphorsheet when the stimulable phosphor sheet is exposed to the stimulatingrays, is detected by the photoelectric read-out means located above theholder, and an image signal (a one surface side image signal) is therebydetected. Also, the light, which is emitted from the other surface sideof the stimulable phosphor sheet when the stimulable phosphor sheet isexposed to the stimulating rays, is detected by the photoelectricread-out means located below the holder, and an image signal (an othersurface side image signal) is thereby detected.

Thereafter, an addition operation is performed on the image signalcomponents of the two image signals having been detected from theopposite surfaces of the stimulable phosphor sheet (i.e., the onesurface side image signal and the other surface side image signal),which image signal components represent corresponding pixels on the onesurface and the other surface of the stimulable phosphor sheet, and anaddition image signal (a superposition image signal) is therebyobtained. With the addition operation, high frequency noise occurring atrandom in each of the one surface side image signal and the othersurface side image signal can be smoothed. Also, since the emitted lightis collected from the two surfaces of the stimulable phosphor sheet, thelight collecting efficiency can be enhanced. As a result, asuperposition image, which has good image quality with an enhancedsignal-to-noise ratio, can be reproduced from the addition image signal.

Also, as techniques for obtaining radiation image information byutilizing stimulable phosphor sheets, or the like, subtractionprocessing (subtraction operation) techniques have heretofore beenknown. With the subtraction processing techniques, a plurality ofradiation images are recorded under different conditions and are thenread out to obtain a plurality of image signals. Thereafter, asubtraction operation is performed on the plurality of the imagesignals, and a subtraction image signal is thereby obtained. In thismanner, a subtraction image corresponding to the difference between theplurality of the radiation images, i.e. a subtraction image in whichonly a pattern of a specific object part (hereinbelow referred to alsoas a pattern of a tissue, a structure, or the like) in the radiationimages has been enhanced or extracted, is obtained. Basically, thesubtraction processing techniques may be classified into a temporal(time difference) subtraction processing technique and an energysubtraction processing technique. The applicant proposed various energysubtraction processing techniques utilizing stimulable phosphor sheetsin, for example, U.S. Pat. Nos. 4,855,598 and 4,896,037.

With the rapid advances made in network technology accompanying rapidadvances made in communication technology and computer technology inrecent years, for example, in the medical fields, there has arisen atendency toward utilization of medical image networks, which act asimage transfer systems. With the medical image networks, various imageforming apparatuses, which are located in examination rooms ofhospitals, or the like, and image output devices, such as image displaydevices and printers, which are located in consultation rooms,laboratories, and the like, are connected to each other through anetwork. In such cases, visible images to be used in making a diagnosiscan be reproduced in the consultation rooms from image signals, whichhave been acquired with the image forming apparatuses located in theexamination rooms.

In the image transfer systems utilizing the networks, and the like, incases where an operation-processed image obtained from the operationprocessing, such as the addition operation or the subtraction operation,is to be outputted by an image output device, the operation-processedimage signal, such as the addition image signal or the subtraction imagesignal, having been obtained from the operation processing hasheretofore been transferred from an image forming apparatus to the imageoutput device, and a visible image has heretofore been outputted by theimage output device in accordance with the transferred image signal.

However, with the transfer technique described above, it is difficult tooperate such that, after the image outputted by the image output deviceis confirmed, parameters for the operation processing, such as theaddition operation or the subtraction operation, are altered, theoperation processing is again performed with the altered parameters, andan image obtained from the operation processing performed with thealtered parameters is again outputted by the image output device.

Therefore, such that the difficulty described above may be eliminated,it may be considered to employ a technique, wherein a plurality of imagesignals having been acquired with the image forming apparatus, i.e. theoriginal image signals, are directly transferred from the image formingapparatus to the image output device, the operation processing, such asthe addition operation or the subtraction operation described above, isperformed in the image output device by utilizing the plurality of thetransferred original image signals and in accordance with predeterminedparameters, and a visible image is outputted in accordance with theoperation-processed image signal obtained from the operation processing.

However, with the technique described above, wherein the plurality ofthe original image signals are transferred to the image output device,and the image output device performs the operation processing andoutputs the operation-processed image, the problems described belowoccur. Specifically, no image is displayed, i.e. a displaying waitingstate occurs, before the operation processing, such as the additionoperation or the subtraction operation, is finished. In the displayingwaiting state, a diagnosis with an image cannot be made. Therefore, anuncomfortable feeling is given to the user, and loss of time occurs.

SUMMARY OF THE INVENTION

The primary object of the present invention is to provide an imagetransfer and output method, wherein an image output waiting state doesnot occur in cases where a plurality of original image signals aretransferred to an image output device such that parameters for operationprocessing, such as an addition operation or a subtraction operation,are capable of being altered on the side of the image output device, andsuch that an image obtained from the operation processing performed withthe altered parameters is capable of being again outputted by the imageoutput device.

Another object of the present invention is to provide an image transferand output system for carrying out the image transfer and output method.

A further object of the present invention is to provide an image signalinput terminal for use in the image transfer and output system.

A still further object of the present invention is to provide an imageoutput terminal for use in the image transfer and output system.

An image transfer and output method in accordance with the presentinvention is characterized by transferring a certain original imagesignal, which is among a plurality of original image signals, to animage output device, and performing image outputting with the imageoutput device in accordance with the certain original image signalbefore operation processing, such as an addition operation or asubtraction operation, is finished and an operation-processed image,such as a superposition image or a subtraction image, thus becomescapable of being outputted on the side of the image output device.

Specifically, the present invention provides an image transfer andoutput method, comprising the steps of:

i) feeding a plurality of original image signals representing radiationimage information, which have been fed out from an image signal inputapparatus, into an operation processing device,

ii) performing predetermined operation processing on the plurality ofthe received original image signals in the operation processing deviceto obtain an operation-processed image signal,

iii) transferring at least one original image signal, which is among theplurality of the original image signals, to an image output device,

iv) performing image outputting with the image output device and inaccordance with the one original image signal having been transferred,

v) after the operation-processed image signal has been obtained from thepredetermined operation processing, feeding the operation-processedimage signal into the image output device, and

vi) performing image outputting with the image output device and inaccordance with the received operation-processed image signal.

The term “transfer” as used herein means the transmission (delivery) ofan image signal from one device to a different device. As the means forthe transfer, one of various techniques may be employed. The transfermeans is not limited to the means utilizing the network described aboveand may be, for example, the means for transmitting an image signal viaa recording medium, such as a CD-ROM or a MO. In cases where the meansfor transmitting an image signal via a recording medium, such as aCD-ROM or a MO, is employed, and, for example, an image signal is to betransferred from the image signal input apparatus to an operationprocessing and image output terminal, which comprises the operationprocessing device and the image output device combined with each other,the image signal input apparatus may be provided with means for storingan image signal on the recording medium, and the operation processingand image output terminal may be provided with means for reading theimage signal from the recording medium.

In the image transfer and output method in accordance with the presentinvention, the image outputting, which is performed with the imageoutput device and in accordance with the one original image signalhaving been transferred, may be conducted in the manner described below.Specifically, for example, in cases where the CR apparatus describedabove is employed as the image forming apparatus, and an additionoperation is performed to display a superposition image, a stimulatingray irradiation surface side image should preferably be firstlydisplayed. The term “stimulating ray irradiation surface side image” asused herein means the image, which is obtained by detecting the lightemitted from the sheet surface on the stimulating ray irradiation sidein cases where the stimulating rays are irradiated from only one surfaceside of the stimulable phosphor sheet. In cases where an energysubtraction operation is performed to display an energy subtractionimage, either one of a high energy image, which is recorded withradiation having a high energy level, and a low energy image, which isrecorded with radiation having a low energy level, may be firstlydisplayed.

Also, in the image transfer and output method in accordance with thepresent invention, the plurality of the original image signals are fedinto an operation processing device, and the predetermined operationprocessing is performed on the plurality of the received original imagesignals in the operation processing device. Specifically, in theoperation processing device, it is sufficient for the operationprocessing to be performed on at least two original image signals amongthe plurality of the received original image signals, and all of theplurality of the received original image signals need not necessarily beutilized in the operation processing. For example, in cases where threeoriginal image signals are fed from the image signal input apparatusinto the operation processing device, the operation processing devicemay perform an addition operation, or the like, on the two originalimage signals among the three received original image signals.

Further, the image signal input apparatus may also feed out an originalimage signal other than the plurality of the original image signalsdescribed above, which are fed into the operation processing device. Forexample, in cases where two original image signals are fed from theimage signal input apparatus into the operation processing device, theimage signal input apparatus may also feed out a third original imagesignal other than the two original image signals.

Furthermore, in the image transfer and output method in accordance withthe present invention, after the operation-processed image signal hasbeen obtained from the predetermined operation processing, theoperation-processed image signal is fed into the image output device.Also, the image outputting is performed with the image output device andin accordance with the received operation-processed image signal.Specifically, after the operation processing has been performed, theimage outputting is performed in accordance with the operation-processedimage signal, which has been obtained from the operation processing.More specifically, the image outputting is firstly performed inaccordance with a certain original image signal among the plurality ofthe original image signals described above. Thereafter, when theoperation-processed image signal has been obtained and it becomespossible to perform the image outputting in accordance with theoperation-processed image signal, the operation-processed imagerepresented by the operation-processed image signal is outputted withthe image output device. In such cases, it is only necessary that, afterthe operation processing is finished, at least the operation-processedimage, such as a superposition image or a subtraction image, bedisplayed. Specifically, the original image, which has been displayedbefore the operation processing is finished, need not necessarily bereplaced by the operation-processed image. For example, before theoperation processing is finished, the original image may be displayedover the entire area of the display screen. After the operationprocessing is finished, the original image and the operation-processedimage may be displayed respectively on halves of the display screen.

The image transfer and output method in accordance with the presentinvention may be modified such that, in cases where the operationprocessing device is located on the side of the image output device,

the plurality of the original image signals are transferred to theoperation processing device, and

the operation processing is performed on the plurality of thetransferred original image signals in the operation processing device.

The term “operation processing device being located on the side of animage output device” as used herein means that the operation processingdevice is located such that the operation-processed image signal, whichis obtained from the operation processing device, is fed into the imageoutput device without the transfer via a network, a recording medium, orthe like, being performed. The operation processing device and the imageoutput device may be combined into an integral body (i.e., an imageoutput terminal provided with operation processing functions).Alternatively, the operation processing device and the image outputdevice may be formed as two independent devices.

Also, the image transfer and output method in accordance with thepresent invention may be modified such that, in cases where theoperation processing device is located on the side of the image signalinput apparatus,

the operation-processed image signal, which has been obtained from theoperation processing device, is transferred to the image output device,and

the image outputting is performed with the image output device and inaccordance with the operation-processed image signal having beentransferred.

The term “operation processing device being located on the side of animage signal input apparatus” as used herein means that the operationprocessing device is located such that the plurality of the originalimage signals having been fed out from the image signal input apparatusare fed into the operation processing device without the transfer via anetwork, a recording medium, or the like, being performed. The operationprocessing device and the image signal input apparatus may be combinedinto an integral body (i.e., an image signal input terminal providedwith operation processing functions). Alternatively, the operationprocessing device and the image signal input apparatus may be formed astwo independent devices.

In cases where the image signal input apparatus, the operationprocessing device, and the image output device are located inindependent forms as in the cases where the apparatus and the devicesare connected with one another through a network, one original imagesignal among the plurality of the original image signals is transferredto the image output device, the plurality of the original image signalsare transferred to the operation processing device, the operationprocessing is performed with the operation processing device and inaccordance with the plurality of the transferred original image signals,and the operation-processed image signal having been obtained from theoperation processing is transferred to the image output device.

The present invention also provides an image transfer and output system,comprising:

i) an image signal input apparatus for feeding a plurality of originalimage signals representing radiation image information,

ii) an operation processing device for performing predeterminedoperation processing on the plurality of the original image signals toobtain an operation-processed image signal,

iii) an image output device for performing image outputting inaccordance with a received original image signal, and

iv) a transfer device for transferring an image signal,

wherein the transfer device transfers at least one original imagesignal, which is among the plurality of the original image signals, tothe image output device, and

the image output device operates such that the image output deviceperforms image outputting in accordance with the one original imagesignal having been transferred and such that, when theoperation-processed image signal is received from the operationprocessing device, the image output device performs image outputting inaccordance with the received operation-processed image signal.

The image transfer and output system in accordance with the presentinvention may be modified such that the operation processing device islocated on the side of the image output device,

the transfer device transfers the plurality of the original imagesignals to the operation processing device, and

the operation processing device performs the operation processing on theplurality of the transferred original image signals.

Also, the image transfer and output system in accordance with thepresent invention may be modified such that the operation processingdevice is located on the side of the image signal input apparatus, and

the transfer device transfers the operation-processed image signal,which has been obtained from the operation processing device, to theimage output device.

The present invention further provides an image signal input terminalfor use in the image transfer and output system in accordance with thepresent invention. Specifically, the present invention further providesan image signal input terminal, comprising:

i) an image signal input apparatus for feeding a plurality of originalimage signals representing radiation image information, and

ii) an operation processing device for performing predeterminedoperation processing on the plurality of the original image signals toobtain an operation-processed image signal.

The present invention still further provides an image output terminalfor use in the image transfer and output system in accordance with thepresent invention. Specifically, the present invention still furtherprovides an image output terminal, comprising:

i) an operation processing device for performing predetermined operationprocessing on a plurality of original image signals to obtain anoperation-processed image signal, and

ii) an image output device for operating such that the image outputdevice performs image outputting in accordance with one original imagesignal among the plurality of the original image signals and such that,when the operation-processed image signal is received from the operationprocessing device, the image output device performs image outputting inaccordance with the received operation-processed image signal.

With the image transfer and output method and the image transfer andoutput system in accordance with the present invention, at least oneoriginal image signal, which is among the plurality of the originalimage signals, is transferred to the image output device, and the imageoutputting is performed with the image output device and in accordancewith the one original image signal having been transferred. After thepredetermined operation processing has been finished in the operationprocessing device, the operation-processed image, such as asuperposition image or a subtraction image, is outputted with the imageoutput device. Therefore, an image outputting waiting state does notoccur before the operation-processed image is displayed. Accordingly,for example, before the operation-processed image is displayed,temporary processing, such as a preliminary diagnosis, can be performedby use of the original image. The feature is advantageous in practice.

Also, operation processing can again be performed by utilizing theplurality of the transferred original image signals, or by utilizing onetransferred original image signal and the operation-processed imagesignal, and with altered parameters for the operation processing, suchas the addition operation or the subtraction operation, and an imageobtained from the operation processing performed with the alteredparameters can again be outputted with the image output device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a first embodiment of the imagetransfer and output system in accordance with the present invention,

FIG. 2 is a perspective view showing an example of a radiation imageread-out apparatus, which acts as an image signal input apparatus in theembodiment of the image transfer and output system and in which atechnique for detecting light emitted from opposite surfaces of astimulable phosphor sheet and thereby detecting two image signals fromthe opposite surfaces of the stimulable phosphor sheet is employed,

FIG. 3 is a block diagram showing operation processing means in anoperation processing and displaying terminal, which is employed in theembodiment of the image transfer and output system,

FIG. 4 is a block diagram showing a second embodiment of the imagetransfer and output system in accordance with the present invention, and

FIG. 5 is a block diagram showing a third embodiment of the imagetransfer and output system in accordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will hereinbelow be described in further detailwith reference to the accompanying drawings.

FIG. 1 is a block diagram showing a first embodiment of the imagetransfer and output system in accordance with the present invention. Asillustrated in FIG. 1, the first embodiment of the image transfer andoutput system in accordance with the present invention comprises animage signal input apparatus 100, and a network 200 acting as a transferdevice. The image transfer and output system also comprises an operationprocessing and displaying terminal 300, which comprises an operationprocessing device 310 and an image displaying device 320 combined intoan integral body and which acts as an image output terminal. The imagedisplaying device 320 is constituted of a cathode ray tube (CRT) displaydevice or a liquid crystal panel display device for outputting a softcopy. Alternatively, in the operation processing and displaying terminal300, the operation processing device 310 and the image displaying device320 may be formed as two independent devices. By way of example, theimage transfer and output system can be utilized as a medical networksystem in a hospital.

As the image signal input apparatus 100, one of various apparatuses,which feeds a plurality of original image signals, may be employed. Forexample, as the image signal input apparatus 100, an image formingapparatus, such as a CT scanner or a CR apparatus, may be utilized.

FIG. 2 is a perspective view showing an example of a radiation imageread-out apparatus, which acts as the image signal input apparatus 100and in which a technique for detecting light emitted from oppositesurfaces of a stimulable phosphor sheet and thereby detecting two imagesignals from the opposite surfaces of the stimulable phosphor sheet isemployed.

As illustrated in FIG. 2, in the radiation image read-out apparatus, astimulable phosphor sheet 1, on which radiation image information hasbeen stored, is placed on endless belts 9 a and 9 b, which are rotatedby motors (not shown). A laser beam source 10, a rotating polygon mirror12, and a scanning lens 19 are located above the stimulable phosphorsheet 1. The laser beam source 10 produces a laser beam 11 acting asstimulating rays, which cause the stimulable phosphor sheet 1 to emitlight in proportion to the amount of energy stored thereon during itsexposure to radiation. The rotating polygon mirror 12 reflects anddeflects the laser beam 11 having been produced by the laser beam source10 and causes the laser beam 11 to scan the stimulable phosphor sheet 1in main scanning directions indicated by the double headed arrow X. Therotating polygon mirror 12 is rotated by a motor (not shown). Thescanning lens 19 converges the laser beam 11, which has been reflectedand deflected by the rotating polygon mirror 12, onto the stimulablephosphor sheet 1 and causes the laser beam 11 to scan the stimulablephosphor sheet 1 at uniform speed. A light guide member 14 a is locatedabove and close to the position that is scanned with the laser beam 11.The light guide member 14 a guides the light, which is emitted by thestimulable phosphor sheet 1 when the stimulable phosphor sheet 1 isscanned with the laser beam 11, from above. Also, a light guide member14 b is located below the position that is scanned with the laser beam11. The light guide member 14 b is located perpendicularly to thestimulable phosphor sheet 1 and guides the emitted light from below. Thelight guide member 14 a is connected to a photomultiplier 15 a forphotoelectrically detecting the emitted light. Also, the light guidemember 14 b is connected to a photomultiplier 15 b for photoelectricallydetecting the emitted light. The photomultiplier 15 a and thephotomultiplier 15 b are connected to logarithmic amplifiers (notshown).

When radiation image signals are to be obtained with the radiation imageread-out apparatus, the stimulable phosphor sheet 1, on which theradiation image information of an object has been stored, is set at apredetermined position on the endless belts 9 a and 9 b. The stimulablephosphor sheet 1, which has been set at the predetermined position, isconveyed in the direction (sub-scanning direction), which is indicatedby the arrow Y, by the endless belts 9 a and 9 b. The laser beam 11,which has been produced by the laser beam source 10, is reflected anddeflected by the rotating polygon mirror 12, which is being driven bythe motor (not shown) and quickly rotated in the direction indicated bythe arrow. The laser beam 11 is then converged by the scanning lens 19onto the stimulable phosphor sheet 1 and is caused to scan thestimulable phosphor sheet 1 in the main scanning directions indicated bythe double headed arrow X. The main scanning directions areapproximately normal to the sub-scanning direction indicated by thearrow Y. When the stimulable phosphor sheet 1 is thus exposed to thelaser beam 11, light in accordance with the stored radiation imageinformation is emitted by the exposed portion of the stimulable phosphorsheet 1. Specifically, light 13 a is emitted from the upper surface sideof the stimulable phosphor sheet 1, and light 13 b is emitted from thelower surface side of the stimulable phosphor sheet 1.

The light 13 a, which has been emitted from the upper surface side ofthe stimulable phosphor sheet 1 impinges upon a light input face of thelight guide member 14 a. The emitted light 13 a enters the light guidemember 14 a from its light input face and is guided through repeatedtotal reflection inside of the light guide member 14 a. The emittedlight 13 a then emanates from a light output face of the light guidemember 14 a and is received by the photomultiplier 15 a. In this manner,the emitted light 13 a is converted by the photomultiplier 15 a into ananalog electric signal S_(A), which is in accordance with the amount ofthe emitted light 13 a, which amount represents the stored radiationimage information. In the same manner as that described above, theemitted light 13 b, which has been emitted from the lower surface sideof the stimulable phosphor sheet 1, is guided inside of the light guidemember 14 b and is photoelectrically detected by the photomultiplier 15b. The emitted light 13 b is converted by the photomultiplier 15 b intoan analog electric signal S_(B). In this manner, two electric signalsS_(A) and S_(B) representing the radiation image information areobtained.

The electric signal S_(A), which has been generated by thephotomultiplier 15 a, and the electric signal S_(B), which has beengenerated by the photomultiplier 15 b, are fed into logarithmicamplifiers (not shown) and are then fed into image processing means (notshown). Ultimately, the electric signal S_(A) is converted into an imagesignal S1, and the electric signal S_(B) is converted into an imagesignal S2. The image signal S1, which has been obtained by detecting thelight 13 a emitted from the upper surface side of the stimulablephosphor sheet 1, will hereinbelow be referred to as the stimulating rayirradiation surface side image signal S1. Also, the image signal S2,which has been obtained by detecting the light 13 b emitted from thelower surface side of the stimulable phosphor sheet 1, will hereinbelowbe referred to as the other surface side image signal S2. An additionoperation may be performed on the stimulating ray irradiation surfaceside image signal S1 and the other surface side image signal S2, and anaddition image signal S3 may thereby be obtained as theoperation-processed image signal.

In a conventional image transfer and output system, the thus obtainedaddition image signal S3 is fed to the network 200. Also, in theconventional image transfer and output system, the addition image signalS3 is transferred and fed into the image displaying device 320, and thesuperposition image represented by the addition image signal S3 isoutputted with the image displaying device 320.

In the first embodiment of the image transfer and output system inaccordance with the present invention, the operation processing device310 for forming the addition image signal S3 is located on the side ofthe image displaying device 320, and the operation processing device 310and the image displaying device 320 are combined into an integral bodyto constitute the operation processing and displaying terminal 300.Also, the addition image signal S3 is not fed to the network 200, andthe stimulating ray irradiation surface side image signal S1 and theother surface side image signal S2 are fed to the network 200 andtransferred through the network 200 to the operation processing device310. In the operation processing device 310, the addition operation isperformed on the thus transferred image signals S1 and S2. Thereafter,the superposition image represented by the addition image signal S3obtained from the addition operation is outputted with the imagedisplaying device 320. The features described above will hereinbelow bedescribed in more detail.

The stimulating ray irradiation surface side image signal S1 and theother surface side image signal S2, which have been fed from the imagesignal input apparatus 100, are transferred through the network 200 tothe operation processing and displaying terminal 300. In such cases,operation parameters for the addition operation may be appended to thestimulating ray irradiation surface side image signal S1 and the othersurface side image signal S2 and may thus be transferred to theoperation processing and displaying terminal 300.

As described above, the operation processing and displaying terminal 300receives the stimulating ray irradiation surface side image signal S1and the other surface side image signal S2. In the operation processingand displaying terminal 300, firstly, the stimulating ray irradiationsurface side image, which is represented by the stimulating rayirradiation surface side image signal S1, is displayed on the imagedisplaying device 320. At this time, a predetermined mark shouldpreferably be displayed in order to indicate that the displayed image isthe one (i.e., the stimulating ray irradiation surface side image)before being subjected to the operation processing, which will bedescribed later.

Simultaneously with the displaying of the stimulating ray irradiationsurface side image, the operation processing device 310 performs theaddition operation on the stimulating ray irradiation surface side imagesignal S1 and the other surface side image signal S2 and forms theaddition image signal S3, which represents the superposition image.

As illustrated in FIG. 3, the operation processing device 310 comprisesmasking operation means 311 for performing a masking operation on thestimulating ray irradiation surface side image signal S1, and maskingoperation means 312 for performing a masking operation on the othersurface side image signal S2. The operation processing means 310 alsocomprises addition means 313 for performing the addition operation on astimulating ray irradiation surface side image signal S1′, which hasbeen obtained from the masking operation, and an other surface sideimage signal S2′, which has been obtained from the masking operation. Inthis manner, the addition operation is performed on the image signalshaving been obtained from the filtering processing with the maskingoperations.

As the filtering processing with the masking operations, one of variousknown filtering processing techniques may be employed. For example, aprocessing technique for performing wavelet transform on an image signalto obtain wavelet transform factor signals of different frequency bandsmay be employed. The processing technique for performing the wavelettransform is disclosed in, for example, Japanese Unexamined PatentPublication No. 7(1995)-319092. In cases where the processing techniquedisclosed in Japanese Unexamined Patent Publication No. 7(1995)-319092is employed, in the addition means 313, the addition operation may beperformed with weight factors appropriate for each of the stimulatingray irradiation surface side and the other surface side and with respectto each of the frequency bands.

After the addition image signal S3 has been formed by the operationprocessing device 310 and has been fed into the image displaying device320, the image displaying device 320 performs the image displaying inaccordance with the addition image signal S3. For example, the imagedisplaying device 320 displays the superposition image, which isrepresented by the addition image signal S3, in lieu of the stimulatingray irradiation surface side image. Alternatively, the stimulating rayirradiation surface side image may be displayed at the left half of thedisplay screen of the image displaying device 320, and the superpositionimage may be displayed at the right half of the display screen of theimage displaying device 320.

As described above, with the first embodiment of the image transfer andoutput system in accordance with the present invention and the operationprocessing and displaying terminal employed in it, before the additionoperation is finished on the side of the operation processing anddisplaying terminal 300 and the superposition image thus becomes capableof being displayed, the stimulating ray irradiation surface side image(the original image), which is represented by the stimulating rayirradiation surface side image signal S1 transferred from the imagesignal input apparatus 100, is displayed by the operation processing anddisplaying terminal 300. Therefore, a displaying waiting state does notoccur before the superposition image is displayed. Accordingly, beforethe superposition image is displayed, temporary processing, such as apreliminary diagnosis, can be performed by use of the displayedstimulating ray irradiation surface side image. Also, the additionoperation can again be performed on the plurality of the transferredoriginal image signals and with altered parameters for the additionoperation on the side of the operation processing and displayingterminal 300, and a superposition image obtained from the additionoperation performed with the altered parameters can again be outputtedby the operation processing and displaying terminal 300. The featuresare advantageous in practice.

In the embodiment described above, before the addition operation isfinished on the side of the operation processing and displaying terminal300 and the superposition image thus becomes capable of being displayed,the stimulating ray irradiation surface side image is displayed by theoperation processing and displaying terminal 300. Alternatively, in lieuof the stimulating ray irradiation surface side image, the other surfaceside image may be displayed before the addition operation is finished.

Also, in the first embodiment described above, the radiation imageread-out apparatus, in which the technique for detecting light emittedfrom opposite surfaces of a stimulable phosphor sheet and therebydetecting two image signals from the opposite surfaces of the stimulablephosphor sheet is employed, is employed as the image signal inputapparatus 100. Also, the operation processing device 310 performs theaddition operation. However, the image transfer and output system inaccordance with the present invention is not limited to the embodimentdescribed above.

For example, as the image signal input apparatus 100, an apparatuscapable of acquiring a high energy image signal, which represents a highenergy image having been recorded with radiation having a high energylevel, and a low energy image signal, which represents a low energyimage having been recorded with radiation having a low energy level, forenergy subtraction processing may be employed. Also, as the operationprocessing device 310, a device for performing a subtraction operationmay be employed. In this manner, before the subtraction operation isfinished on the side of the operation processing and displaying terminal300 and an energy subtraction image having been obtained from thesubtraction operation thus becomes capable of being displayed, the highenergy image, which is represented by the high energy image signaltransferred from the image signal input apparatus 100, or the low energyimage, which is represented by the low energy image signal transferredfrom the image signal input apparatus 100, may be displayed by theoperation processing and displaying terminal 300. After the subtractionoperation is finished, the energy subtraction image, which has beenobtained from the subtraction operation, may be displayed by theoperation processing and displaying terminal 300.

A second embodiment of the image transfer and output system inaccordance with the present invention will be described hereinbelow.FIG. 4 is a block diagram showing a second embodiment of the imagetransfer and output system in accordance with the present invention.

In the first embodiment of the image transfer and output systemdescribed above, the operation processing device 310 is located on theside of the image displaying device 320. In the second embodiment of theimage transfer and output system in accordance with the presentinvention, the operation processing device 310 for obtaining theaddition image signal S3 is located on the side of the image signalinput apparatus 100, and an

image signal input terminal 110 is constituted, in which the imagesignal input apparatus 100 and the operation processing device 310 arecombined with each other into an integral body. Also, the addition imagesignal S3 and the stimulating ray irradiation surface side image signalS1 are fed into the network 200 and transferred through the network 200.In this manner, the stimulating ray irradiation surface side image,which is represented by the stimulating ray irradiation surface sideimage signal S1 having been transferred, or the superposition image,which is represented by the addition image signal S3 having beentransferred, is outputted with the image displaying device 320.Alternatively, the image signal input apparatus 100 and the operationprocessing device 310 may be formed as two independent apparatus anddevice. Basically, the second embodiment operates in the same manner asthat in the first embodiment described above, except for the featuresdescribed below.

Specifically, of the stimulating ray irradiation surface side imagesignal S1 and the other surface side image signal S2, which have beenfed from the image signal input apparatus 100, the stimulating rayirradiation surface side image signal S1 is transferred through thenetwork 200 to the image displaying device 320. In the image displayingdevice 320, firstly, the stimulating ray irradiation surface side image,which is represented by the stimulating ray irradiation surface sideimage signal S1, is displayed. At this time, as in the first embodimentdescribed above, a predetermined mark should preferably be displayed inorder to indicate that the displayed image is the stimulating rayirradiation surface side image.

Simultaneously with the displaying of the stimulating ray irradiationsurface side image, the stimulating ray irradiation surface side imagesignal S1 and the other surface side image signal S2, which have beenfed from the image signal input apparatus 100, are immediately fed intothe operation processing device 310, and the addition image signal S3 isformed.

After the addition image signal S3 has been formed by the operationprocessing device 310, the addition image signal S3 is transferredthrough the network 200 to the image displaying device 320.

When the addition image signal S3 is transferred from the operationprocessing device 310 to the image displaying device 320, the imagedisplaying device 320 performs the image displaying in accordance withthe addition image signal S3. For example, the image displaying device320 displays the superposition image, which is represented by theaddition image signal S3, in lieu of the stimulating ray irradiationsurface side image. Alternatively, the stimulating ray irradiationsurface side image may be displayed at the left half of the displayscreen of the image displaying device 320, and the superposition imagemay be displayed at the right half of the display screen of the imagedisplaying device 320.

As described above, with the second embodiment of the image transfer andoutput system in accordance with the present invention and the imagesignal input terminal employed in it, before the addition operation isfinished in the operation processing device 310 and the addition imagesignal S3 representing the superposition image becomes capable of beingtransferred to the image displaying device 320, the stimulating rayirradiation surface side image (the original image signal), which isrepresented by the stimulating ray irradiation surface side image signalS1 having been transferred from the image signal input apparatus 100, isdisplayed on the image displaying device 320. Therefore, as in the firstembodiment described above, a displaying waiting state does not occurbefore the superposition image is displayed.

Also, the other surface side image signal S2 can be reconstructed fromthe stimulating ray irradiation surface side image signal S1 and theaddition image signal S3, which have been transferred. Further, by theutilization of the stimulating ray irradiation surface side image signalS1, which has been transferred, and the other surface side image signalS2, which has thus been reconstructed, the parameters for the additionoperation can be altered, and the addition operation can again beperformed with the altered parameters for the addition operation. Inthis manner, a superposition image obtained from the addition operationperformed with the altered parameters can again be outputted.

In the second embodiment, as in the first embodiment described above,the other surface side image may be firstly displayed in lieu of thestimulating ray irradiation surface side image. Also, an energysubtraction image may be displayed in lieu of the superposition image.

A third embodiment of the image transfer and output system in accordancewith the present invention will be described hereinbelow. FIG. 5 is ablock diagram showing a third embodiment of the image transfer andoutput system in accordance with the present invention.

With reference to FIG. 5, in the third embodiment of the image transferand output system in accordance with the present invention, the imagesignal input apparatus 100, the operation processing device 310, and theimage displaying device 320 are connected with one another through thenetwork 200. Also, the stimulating ray irradiation surface side imagesignal S1 and the other surface side image signal S2 are fed to thenetwork 200 and transferred through the network 200. The stimulating rayirradiation surface side image signal S1 is fed into the imagedisplaying device 320. Further, the stimulating ray irradiation surfaceside image signal S1 and the other surface side image signal S2 are fedinto the operation processing device 310. The addition image signal S3,which has been obtained from the addition operation performed by theoperation processing device 310, is transferred through the network 200and fed into the image displaying device 320. In this manner, thestimulating ray irradiation surface side image or the superpositionimage is outputted. Basically, the third embodiment operates in the samemanner as that in the first and second embodiments described above,except for the features described below.

Specifically, the stimulating ray irradiation surface side image signalS1 and the other surface side image signal S2, which have been fed fromthe image signal input apparatus 100, are fed to and transferred throughthe network 200. The image displaying device 320 receives thestimulating ray irradiation surface side image signal S1 and the othersurface side image signal S2, which have thus been transferred. In theimage displaying device 320, firstly, the stimulating ray irradiationsurface side image, which is represented by the stimulating rayirradiation surface side image signal S1, is displayed. At this time, asin the first and second embodiments described above, a predeterminedmark should preferably be displayed in order to indicate that thedisplayed image is the stimulating ray irradiation surface side image.

Simultaneously with the displaying of the stimulating ray irradiationsurface side image, the stimulating ray irradiation surface side imagesignal S1 and the other surface side image signal S2, which have beenfed from the image signal input apparatus 100, are fed through thenetwork 200 into the operation processing device 310, and the additionimage signal S3 is formed.

After the addition image signal S3 has been formed by the operationprocessing device 310, the addition image signal S3 is transferredthrough the network 200 to the image displaying device 320.

When the addition image signal S3 is transferred from the operationprocessing device 310 to the image displaying device 320, the imagedisplaying device 320 performs the image displaying in accordance withthe addition image signal S3. For example, the image displaying device320 displays the superposition image, which is represented by theaddition image signal S3, in lieu of the stimulating ray irradiationsurface side image. Alternatively, the stimulating ray irradiationsurface side image may be displayed at the left half of the displayscreen of the image displaying device 320, and the superposition imagemay be displayed at the right half of the display screen of the imagedisplaying device 320.

As described above, with the third embodiment of the image transfer andoutput system in accordance with the present invention, before theaddition operation is finished in the operation processing device 310and the addition image signal S3 representing the superposition imagebecomes capable of being transferred to the image displaying device 320,the stimulating ray irradiation surface side image (the original imagesignal), which is represented by the stimulating ray irradiation surfaceside image signal S1 having been transferred from the image signal inputapparatus 100 to the image displaying device 320, is displayed on theimage displaying device 320. Therefore, as in the first and secondembodiments described above, a displaying waiting state does not occurbefore the superposition image is displayed.

Also, as in the second embodiment described above, the other surfaceside image signal S2 can be reconstructed from the stimulating rayirradiation surface side image signal S1 and the addition image signalS3, which have been transferred. Further, by the utilization of thestimulating ray irradiation surface side image signal S1, which has beentransferred, and the other surface side image signal S2, which has thusbeen reconstructed, the parameters for the addition operation can bealtered, and the addition operation can again be performed with thealtered parameters for the addition operation. In this manner, asuperposition image obtained from the addition operation performed withthe altered parameters can again be outputted.

In the third embodiment, as in the first embodiment described above, theother surface side image may be firstly displayed in lieu of thestimulating ray irradiation surface side image. Also, an energysubtraction image may be displayed in lieu of the superposition image.

The image transfer and output system in accordance with the presentinvention is not limited to the embodiments described above and may beembodied in various other ways.

For example, in the embodiments described above, the image displayingdevice 320 for outputting a soft copy, such as a CRT display device or aliquid crystal panel display device, is employed as the image outputdevice. Alternatively, for example, a device for outputting a hard copy,such as a laser printer, may be employed as the image output device. Insuch cases, before an operation-processed image (such as a superpositionimage or an energy subtraction image), which is to be obtainedultimately, becomes capable of being outputted with the laser printer,the stimulating ray irradiation surface side image or the other surfaceside image may be outputted with the laser printer. Alternatively,besides the laser printer, an image displaying device, such as a CRTdisplay device, may be utilized. In this manner, the stimulating rayirradiation surface side image or the other surface side image may bedisplayed on the image displaying device. The outputting of a singlehard copy image requires a longer time than the outputting of a softcopy image. However, in cases where the image displaying device, such asa CRT display device, is utilized besides the laser printer, thestimulating ray irradiation surface side image, or the like, can bedisplayed on the CRT display device before the entire area of thesuperposition image is outputted with the printer. Therefore, in suchcases, preliminary confirmation of the image can be made by seeing theimage displayed on the CRT display device.

In addition, all of the contents of Japanese Patent Application Nos.11(1999)-185350 and 2000-178384 are incorporated into this specificationby reference.

1. An image transfer and output method, comprising the steps of: i)feeding a plurality of original image signals representing radiationimage information, which have been fed out from an image signal inputapparatus, into an operation processing device, ii) performingpredetermined operation processing on the plurality of the receivedoriginal image signals in the operation processing device to obtain anoperation-processed image signal, iii) transferring at least oneoriginal image signal, which is among the plurality of the originalimage signals, to an image output device, prior to theoperation-processed image signal being obtained from the predeterminedoperation processing, iv) performing image outputting with the imageoutput device and in accordance with the one original image signalhaving been transferred, v) after the operation-processed image signalhas been obtained from the predetermined operation processing, feedingthe operation-processed image signal into the image output device, andvi) performing image outputting with the image output device and inaccordance with the received operation-processed image signal.
 2. Amethod as defined in claim 1 wherein, in cases where the operationprocessing device is located on the side of the image output device, theplurality of the original image signals are transferred to the operationprocessing device, and the operation processing is performed on theplurality of the transferred original image signals in the operationprocessing device.
 3. The method of claim 2, wherein the plurality oforiginal image signals are transferred to the operation processingdevice from the image signal input apparatus through a network.
 4. Amethod as defined in claim 1 wherein, in cases where the operationprocessing device is located on the side of the image signal inputapparatus, the operation-processed image signal, which has been obtainedfrom the operation processing device, is transferred to the image outputdevice, and the image outputting is performed with the image outputdevice and in accordance with the operation-processed image signalhaving been transferred.
 5. A method as defined in claim 1, whereinperforming image outputting with the image output device and inaccordance with the one original image signal having been transferred isperformed prior to the operation-processed image signal being obtainedfrom the predetermined operation processing.
 6. A method as defined inclaim 1, wherein the step ii) comprises adding an image signal obtainedfrom an upper surface side of a stimulable phosphor sheet to an imagesignal obtained from a lower surface side of the stimulable phosphorsheet.
 7. A method as defined in claim 6, wherein the step ii) furthercomprises performing a masking operation on each of the image signalsobtained from the upper and lower surface sides of the stimulablephosphor sheet.
 8. A method as defined in claim 1, wherein, in said stepvi, an image represented by the received operation-processed imagesignal is displayed on the image output device together with an imagerepresented by said one original image signal.
 9. A method as defined inclaim 1, wherein first and second original image signals are output inparallel from said image signal input apparatus.
 10. An image transferand output method, comprising: i) feeding a plurality of original imagesignals representing radiation image information, which have been fedout from an image signal input apparatus, into an operation processingdevice, ii) performing predetermined operation processing on theplurality of the received original image signals in the operationprocessing device to obtain an operation-processed image signal whichrepresent the radiation image information, iii) feeding theoperation-processed image signal into an image output device, iv)performing image outputting with the image output device and inaccordance with the received operation-processed image signal, whereinv) at least one of said plurality of original image signals istransferred to the image output device, before the operation-processedimage signals is obtained from the predetermined operation-processing,and vi) image outputting is performed with the image output device andin accordance with said at least one original image signal having beentransferred, before the operation-processed image signal has beenobtained and image outputting has been capable of being performed withthe image output device and in accordance with said obtainedoperation-processed image signal.
 11. A method as defined in claim 10,wherein the plurality of the original image signals comprise a highenergy image signal, which represents a high energy image having beenrecorded with radiation having a high energy level, and a low energyimage signal, which represents a low energy image having been recordedwith radiation having a low energy level, for energy subtractionprocessing, and the operation-processed image signal represents anenergy subtraction image.